In manufacturing cabinets, shelving, scaffolding, furniture, and other articles from wood or wood-like materials, adjoining components or pieces of wood are often secured together with dowels and often an adhesive, such as woodworking glue. Conventionally, dowels have been made of wood, but metal and plastic dowels also are known.
In common use, openings or dowel receiving cavities (i.e., the female member) are formed in each of the respective components, e.g. pieces of wood or wood-like material, which are to be joined together. When the pieces of wood or wood-like material are assembled, an adhesive is often injected into the opening, or dowel receiving cavity (female member). The dowel (i.e., the male member) is then inserted into the cavity and can be held in place by a friction fit and/or the adhesive. For related technology, please see U.S. Pat. Nos. 6,267,527 and 6,871,681.
Forming a secure dowel joint generally requires among other things, a tight press fit between the dowel (male member) and the sidewalls of the dowel receiving cavity (a complimentarily configured female member or dowel hole) for strong frictional or mechanical bonding, together with a substantially evenly distributed layer of adhesive between the dowel and the sidewalls of the hole for strong chemical bonding.
One of the problems associated with this technique is adequately obtaining a uniform layer of adhesive along the length of the dowel. The tight frictional contact between the sidewalls of the hole and the outer surface of the dowel often interferes with the attempt to form an evenly distributed adhesive layer. Indeed, after the dowel has been inserted, there frequently is an unsightly build up of an adhesive residue around the outer lip of the hole which must in some instances, for example in the manufacture of quality furniture, be removed.
In one prior art approach a liquid resorcinol-formaldehyde resin along with an optional hardener were placed into the dowel receiving cavity followed by insertion of the dowel. Again, this approach often resulted in an uneven distribution of the adhesive between the surfaces of the dowel and the dowel receiving cavity and thus a reduced strength of bonding and also in the expression of excess adhesive from the dowel receiving cavity. Depending on the application (e.g., in the manufacture of fine furniture, or in applications where the surface of the component may come in contact with foods), the expression of the resorcinol-formaldehyde resin adhesive from the dowel receiving cavity may be particularly problematic.
To avoid this problem, it has been suggested (see U.S. Pat. No. 5,338,569-Hatch) to use pre-glued dowels, i.e., dowels that have been coated with a water soluble adhesive or glue. In this approach, water can be applied to the dowel cavity (female member) and the dowel itself also can be pre-moistened to activate (re-solubilize) the glue as the dowel is inserted into the cavity.
In U.S. Patent Application Publication 2008/0115699 an all wood pallet design is described that employs wooden dowels for its assembly.
The present invention focuses on an improved adhesive-coated dowel and a method of using the dowel that facilitates the connection of separate components effectively and efficiently. The adhesive-coated dowel and related method has particular utility in connection with the all wood pallet design of U.S. Patent Application Publication 2008/0115699, the entire disclosure of which is incorporated herein by reference.